Adding email_tfa.settings to config ignore fails to persist

Problem/Motivation

Adding email_tfa.settings to config ignore fails to persist.

Steps to reproduce

Install email_tfa and config_ignore modules
Navigate to the config_ignore configuration page (/admin/config/development/configuration/ignore) and add email_tfa.settings, then export config. This should export a new file, config/default/config_ignore.settings.yml
Navigate to the config sync page (/admin/config/development/configuration) and you should see email_tfa.settings listed in the ignore section
Navigate to the Email TFA Settings page (admin/config/people/email-tfa) and make any change
Navigate back to the config sync page (/admin/config/development/configuration). It will show there is a change to the email_tfa settings, and now the email_tfa.settings value is removed from the ignore section of the page where it was there prior to making new Email TFA settings changes.

I thought there might link to the fact that there is a mis-spelling of "verify" in a few places. It's spelled "verifiy" in the email_tfa.routing.yml and EventSubscriber/EmailTfaSubscriber.php files, but correcting them has proven ineffective in resolving this.

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes